Weft-straightening apparatus



1949. J. D. ROBERTSON 2,461,084

WEFT STRAIGHTENING APPARATUS Filed Jan. 15, 1948 2 Sheets-Sheet l V a efiw m 1949. J. D. ROBERTSON 4 2,461,084

WEFT-STRAIGHTENING APPARATUS Filed Jan. 15, 1948 2 Sheets-Sheet 2 ii 62 a Patented Feb. 8, 1949 WEFT-STRAIGHTENING APPARATUS John D. Robertson, 'launton, Masa, assignor to Mount Hope Machinery Company, Taunton, Mass, a corporation of Massachusetts Application January 15, 1948, Serial. No. 2,393

14 Claims.

This invention relates to improvements in ap-/ .paratus for restoring skewed weft threads in a travelling web of cloth to a proper perpendicular relationship to the warp threads as the web is guided on a predetermined course toward a tenter frame or other item of finishing room equipment. More particularly the invention provides improvements in weft-straighteners of the general type having a pivoted roll which may be moved about its pivot to efiect an increase in the length of the path of travel of one edge portion of a travelling web and a simultaneous decrease in the length of the path of travel of the opposite edge portion of the web.

Pivoted roll weft-straighteners are well known items of finishing room equipment, yet the tilting roll principle of their operation involves problems to avoid objectionable lateral crawling of a web along the tilted roll because of its tilt relative to the normal plane of approach of the web thereto, and to avoid slippage of the web on a roll whose angle of tilt may be substantial. Lateral slip of a web on such a tilted roll introduces objectionable longitudinal wrinkles, and slippage once started may result in a lateral collapsing of the web at one end region of the tilted roll.

It is among the objects of my present invention to provide a tilting roll weft-straightener having means associated with the tilting roll for positively preventing any lateral slip of the web on the tiltable roll in every position thereof. I provide means for gripping the opposite edge regions of the web approaching the tiltable roll and mount the gripping means for movement with the tiltable roll so that the gripping means maintains the portion of the web immediately passing to the roll always in the same relation to the roll regardless of whether the roll is tilted little or much or none. at all.

Another object is to provide a tiltable roll weitstraightener wherein cloth guider rolls engage opposite edge portions of a web approaching the tiltable roll for delivering a full spread portion of the web to the tiltable roll, and wherein the guider rolls continue substantially in the same delivering relation to the tiltable roll in all posi- 1 2 opposite edge regions of the web approaching the tiltable roll and mounted for movement with the tiltable roll about the axis oi. the tiltable roll.

It is moreover, my purpose and object generally to improve the structure and operative effectiveness of weft-straightening apparatus of the tiltable roll general type.

In the accompanying drawings:

Fig. 1 is a diagrammatic perspective view of weft-straightening apparatus embodying features of my invention;

Fig. 2 is a plan view looking down at the guider units and tiltable roll of Fig. 1, portions being broken away;

Fig. 3 is a side elevation of the mechanism of Fig. 2;

Fig. 4 is an elevational view looking toward the right at the mechanism of Figs. 1-3; and

Fig. 5 is a diagrammatic representation of my improved mechanism showing the tiltable roll and the guider rolls in tilted positions which are represented by dotted lines, and showing the resulting displacement of the oncoming web.

Referring to the drawings, a web of cloth "I is represented in Fig. 1 as travelling, in the direction of the arrows, around the idler roll l2, tiltable roll M, and idler roll l6, from which latter roll the web may pass to a tenter frame or other item of finishing room equipment.

The idler rolls l2, I6, may be rotatably mounted at their ends in any suitable bracket bearings or the like, not shown, and the web of cloth III, in the illustrated embodiment, approaches the guide roll l2 generally in a vertical plane, passing around roll l2 and thence generally in a horizontal plane to the tiltable roll it, although this generally horizontal run of the cloth between rolls I2, it may be twisted out of its normal plane by tilting the roll I4 about its horizontal axis of tilting at l8. The web is shown passing from tiltable roll l4 generally in a vertical plane to the idler roll l6, after having made a ninety degree turn around the tiltable roll II.

The length of the tilting roll may vary between fifty inches and one hundred twenty inches depending upon the widths of cloth to be handled, and the amount of permissible tilting of roll ll ordinarily is such that its axis may be set with inclination up to thirty degrees from horizontal in either of two opposite directions in its vertical plane, thereby to bring either end of the roll above or below the normal horizontal plane of the web. In order to permit such a range of tilting of roll H without a disastrous amount of distortion of the run of the web between rolls l2 and I4, it is a practical necessity that the rolls l2 and I4 shall be spaced apart a substantial distance which customarily will be not less than fifty inches.

Heretofore, however, even when the rolls l2 and i4 have been spaced apart fifty inches or more, there has been a strong tendency toward slippage of the web on the tiltable roll when the tilt of the roll has been substantial. The tendency to slip on the tilted roll has been greater with some cloth textures than with others, and when slippage has occurred, longitudinal wrinkling of the web has resulted and the web not infrequently will collapse into a bunched mass at the lower end portion of the tilted roll.

Efforts have been made to avoid this slippage of the web on the tilted roll of a weft-straightener by employing conventional cloth guiders for maintaining the full spread of the cloth as the web approaches the idler roll l2. This tends to preserve the full spread at roll I2 but has been ineffective for preventing slip of the web at the tiltable roll l4. Ordinarily such cloth guiders comprise a coacting pair of rolls at each marginal region of the travelling web, the rolls of each pair engaging opposite sides of the web and being mounted on' an axis transverse of the plane of the engaged web for automatic swinging of the coacting rolls in the plane of the engaged web. When the coacting rolls are set with their axes at right angles to the direction of travel of the web, the coacting guider rolls have no spreading effect on the web. But, when the inner ends of the guider rolls are set in advance of their outer ends, in the direction of travel of the web, the guider rolls act to spread the web laterally to its maximum width. Heretofore, however, the guider rolls have been at adjustably fixed positions and it has been quite impracticable to locate them close enough to the tiltable roll so that the guiders'could maintain the full spread of the web on the tiltable roll in all positions of tilting thereof. Prior attempts to locate conventional automatic guiders between the guide roll l2 and the tiltable roll have been unsuccessful because tilting of the roll would distort the web to an extent suflicient to pull the web out of the gripof the guiders or, at least, would render the guiders ineffective for maintaining a desired spread condition of the web.

According to my present invention, the tiltable roll I 4 is mounted at its opposite ends in a tiltable frame 26 which is pivotally mounted at l8 on a suitable support 22. In the embodiment of Fig. 1, the axis is is in a horizontal plane, and it is a feature of importance that axis is is in the same horizontal plane as the portion of the web which is about to engage the tiltable roll, as best seen in Fig. 3. This, in conjunction with the approximate ninety degree engagement of the web around the tiltable roll l4, minimizes any tendency of the web to crawl laterally on roll l4 due to its tilt, and apart from actual slippage.

I ensure that the web will always come to the tiltable roll l4 in a plane parallel to the axis of roll l4 regardless of the degree of tilt or absence of tilt of the roll H, by mounting guider rolls 24, 26 on the tiltable frame 20 so that the guider rolls tilt with tiltable roll 26 and remain constantly in positions to maintain the portion of the web between the guiders and the tiltable roll I4 always parallel with the axis of roll l4 and always in a relation to roll M such that the guiders automatically maintain a full spread condition of the web on roll l4 regardless of whether the roll is tilted little or much or none at all.

The guider rolls 24, 28 preferably will be spaced from tiltable roll 14 not substantially more than twelve inches, assuming guide roll l2 to be spaced at least fifty inches from tiltable roll l4, so that the roll l4 may be tilted as much as thirty degrees from horizontal without introducing a disturbing amount of distortion or twisting of the portion of the web between guide roll I2 and the guider rolls 24, 26.

The tiltable frame 20 has side portions 28 in which the ends of the tiltable roll M are suitably journalled, and each side portion extends downwardly to a relatively wide terminal part in which the ends of two guide bars or rods 30 are secured. The guide bars 30 extend in spaced parallelism from the terminal part of one side portion 28 of the frame to the similar terminal part of the other side portion 28 of the frame. Two separate carriages 32, 34 are slidably mounted on the guide bars 30 toward opposite ends thereof, and a block 36 is fixed in a position at a mid-location along their extent in which the .unthreaded central portion of a right and left hand screw 38 is rotatably anchored, with the opposite ends of the screw journalled in bearings in the terminal parts of the opposite side portions 28 of frame 20. The right hand threaded portion of the screw 38 extends through and has threaded engagementwith one of the carriages 32, 34 and the left hand threaded portion of the screw 38 similarly has threaded engagement with the other carriage, so that the carriages may be adjusted toward or from each other by rotating screw 38 by means of the hand wheel 40 provided on one end of the screw.

Each carriage 32, 34 has a projecting support thereon, indicated respectively at 33 and 35, for

mounting one of the guider units, each guider unit having a base 42 rigidly secured to one of the projecting supports 33, 35 as by the screws 44. Inasmuch as the two guider units are the same excepting that they are right and left hand units respectively, the following description of one of the units will be equally applicable to the other.

The rolls 24, 26 of each guider unit are carried on a swinging arm 46 which is pivotally mounted at 48 on one of the bases 42. The axis of swinging of arm 46 is perpendicular to the plane of that portion of the web between the guider rolls and the tiltable roll l4, and this axis, in the disclosed embodiment, is located below the rolls and at a mid-location along their extent in the common vertical plane of the axes of the two rolls. Arm 46 extends from its axis is general direction parallel with the plane of the engaged web at the under side of the latter and, at a location beyond the outer ends of the rolls, arm 46 turns sharply upwardly and has the upwardly extending part 46' on which the rolls are mounted, the roll 26 having a fixed axial support on arm extension 46' and the roll 24 being mounted in a bracket toward the forward end of the extension 46" for movement toward and from roll 26 about an axis 50 which is parallel with the axis of roll 24 and adjustable on its block mount into or out of parallelism with roll 26 by means of set screw 52 and clamping screws 54.

Automatic swinging of the guider rolls 24, 26 in response to lateral departures of an edge of the travelling web from a predetermined path may be effected by any of the known devices for this purpose, the particular means herein representd having a brake member 56 coacting with a pair of brake rings 58, 60 as disclosed in my Patent No. 2,422,369, dated June 17, 1947, to which patent reference is made for a more detailed description of the herein represented cloth guiders. As disclosed in my said patent, roll 26 is made in three I sections, and brake member 56 is carried within a yoke 52 pivoted at 64 on a bracket 68 which projects upwardly from the swinging arm it.

In the operation of each cloth guider, the brake member 56 is shifted to neutral position or into engagement with brake ring 58 by means of a bell-crank lever 58 which is responsive to outward travel of a selvage between the rolls 24, 26. Lever 68 has means thereon providing V-arms 68 within which a selvage of the travelling web of cloth is adapted to engage to actuate the lever if the selvage moves outward a predetermined amount, and the lever actuations effect an applying or releasing of the brake, as more particularly described in my said Patent No. 2,422,369, with a coil spring I tending to balance the rolls in or close to a position at right angles to the direction of travel of the web. However, in my said patent the guider rolls swing on axes which are horizontal, with gravity tending to tilt the rolls in one direction and with a spring opposing gravity to attain a generally balanced condition of the rolls. When the axis of swinging of the rolls is vertical as in my presently disclosed embodiment, a much lighter spring III will serve to maintain the desired approximate balancing of the rolls, or two oppositely pulling springs may be employed, properly adjusted as to tension to maintain the desired balancing of the rolls.

The tiltable frame 20, carrying the tilting roll I4 and the guider rolls 24, 26, may be tilted by any suitable means such as the screw 12 threadedly engaging a nut 14 in a slotted bracket 16 on frame 20 to one side of the pitvotal axis I8 of the frame. The screw 12 may have a handle I8 at one end for manual tilting of the frame but preferably the screw will be motor driven in response to means for detecting skew and the direction and extent thereof, for which purpose a reversible motor 80 is shown with reduction gear connection at 82 to screw 12.

It will be apparent from the foregoing description, that the cloth guider rolls 24, 26 operate automatically to maintain the web of cloth full spread as it passes to the tiltable roll II and to hold it full spread on the tilting roll regardless of the position of the tiltable roll. Inasmuch as the guider rolls move with the tiltable roll, that portion of the web between the guider rolls and the tiltable roll always is in a plane parallel to the plane of the tiltable roll axis, so that the cloth always comes to the tiltable roll in the same relation. Yet the distortion or twist of the run of the cloth between the fixed guide roll 12 and the guider rolls 24, 26 is not substantially more than would be the case were the guider rolls absent. Actually, the invention effectively solves a problem which has considerably restricted the field of practical utility of tiltable roll weft-straighteners.

While I have illustrated the invention in an embodiment wherein the tiltable roll and the guiders act on a generally horizontal run of a travelling web, it should be understood that the guiders may equally well act on a generally vertical run of a travelling web. For example, the tiltable roll might be at the place of the fixed guide roll IS in Fig. 1, mounted for tilting in the horizontal plane of its axis, with the guider rolls mounted on the tiltable frame and located a little below the tiltable roll, and with a fixed guide roll at the place of the tiltable roll in Fig. 1. The operation would be generally the same as has been described excepting that the tiltable roll and guider rolls would act on the vertical run of the web rather than on the horizontal run. In such a case, the balancing springs of the guider units would be of strength capable of resisting the tilting tendency of gravity, similar to the disclosure in my said Patent No. 2,422,369.

IKclaim as my invention:

1. In a weft-straightening apparatus, a frame, a web-engaging member having opposite end portions mounted on said frame, means at a midlocation along the frame in the general direction of extent of said member pivotally supporting the frame for movements of the opposite ends of said member in opposite directions away from a predetermined plane, and means carried on said frame for engaging opposite edge portions of a web approaching said web-engaging member and adapted to hold the opposite edge portions of the web against slippage on said member when the opposite ends of said member are moved in opposite directions away from said predetermined plane. Y

2. Weft-straightening apparatus comprising a pivotally mounted web-engaging member, means for guiding a web to said member in an approach plane and for guiding the web leaving said mem- :ber in a plane at right angles to the said approach plane, means pivotally mounting said web-engaging member for movement of the opposite ends thereof simultaneously in opposite directions away from said approach plane, webguiding means for engaging the opposite sides of the web at opposite edge regions thereof and at a portion of the web which is approaching said web-engaging member in said approach plane, and means supporting said web-guiding means for movement with said web-engaging member about the pivotal axis of the latter.

3. In a weft-straightening apparatus having a pivotally mounted Weft-straightening web-engaging roll and means for moving the roll about its pivot, the combination therewith of web-guiding means for engaging opposite edge regions of a portion of a travelling Web of cloth which is approaching said roll, and means supporting said web-guiding means for movement with said roll about its said pivot.

4. Weft-straightening apparatus comprising a pivotally mounted weft-straightening web-engaging roll, fixed web-guiding means for guiding a web of cloth in one plane to said roll and for guiding the web leaving saidroll in a plane at right angles to the first mentioned plane, movable web-guiding means for engaging opposite edge regions of the web as it approaches said roll, and means mounting said roll and said movable web-guiding means for movement in unison about a common pivot, thereby to increase the path of travel of one edge of the web between said fixed web-guiding means while the portion of the web between said movable web-guiding means and said roll is maintained always in a plane parallel to the longitudinal axis of said roll.

5. Weft-straightening apparatus comprising a weft-straightening web-engaging roll, a guide roll fixed in position in substantially spaced general parallelism with said weft-straightening roll for guiding a travelling web of cloth in a predetermined plane to the latter said roll, a second guide roll fixed in position in substantially spaced general parallelism with said weft-straightening roll for guiding the web of cloth leaving the latter said roll in a plane at right angles to said predetermined plane, web-guiding means for en- I said roll in right-angularly related planes, webguiding means for engaging opposite edge reions of the web as the web advances to said roll, a frame carrying both said roll and saidweb-guiding means, and means pivotally supporting said frame for movement about an axis located midway between the ends of said roll in the plane of the web approaching said roll.

7. Weft-straightening apparatus comprising a -\weft-straightening web-engaging roll, means for guiding -a travelling web of cloth to and from said roll in right-angularly related planes, a pair of cloth-guiding rolls engaging the opposite sides ofthe web at each of two opposite edge regions ofthe web as the advancing web approaches the weft-straightening roll, a frame carrying said weft-straightening roll and said cloth-guiding rolls, means pivotally supponting each said pair of cloth-guiding rolls on said frame for movement about separate axes which are generally perpendicular to the plane of approach of the web to thepyeft-straightening roll, and means pivotally mounting said frame for movements about an axis located/midway between the ends of the weftestraightening roll and in the said plane'o'f approach of the web to the latter said roll.

8. In a weft-straightening apparatus, the

V combination of a weft-straightening roll and means' for maintaining the lateral spread of a web of cloth advancing to said roll, a common support for said roll and said maintaining means, and means pivotally mounting said support for movement about an axis transverse of the roll axis and located midway between the ends of said roll and approximately in the plane of the web approaching said roll.

9. Weft-straightenin apparatus comprising a weft-straightening roll, a pair of web-guiding rolls close beside one end portion of the weftstraightening roll, a generally oppositely disposed pair of web-guiding rolls close beside the other end portion of the weft-straightening roll, a frame carrying all of said rolls, and means pivotally supporting the frame for movement of all of said rolls in unison about a common axis whereby the relations of all of said rolls to each other continue the same in all positions of the frame.

10. Weft-straightening apparatus comprising a weft-straightening roll, a pair of web-guiding rolls close beside one 'end portion of the weftstraightening roll, a generally oppositely disposed pair of web-guiding rolls close beside the other end portion of the weft-straightening roll, a frame carrying all of said rolls, means pivotally mounting each said pair of web-guiding rolls on the frame for independent movements about parallel axes located in a plane in which the axes of both rolls of each pair have common extent, and means pivotally supporting the frame for movements about an axis disposed transversely of the pivotal axes of said pairs of webguiding rolls and located midway between the ends of the weft-stramhtening roll in a plane which is generally tangent to surface portions of all of said rolls.

11. Weft-straightening apparatus comprising a weft-straightening roll, a pair of web-guiding rolls close beside one end portion of the weftstraightening roll, a generally oppositely disposed pair of web guiding rolls close beside the other end portion of the weft-straightening roll, a frame carrying all of said rolls, said pairs of web-guiding rolls being adapted to guide a travelling web of cloth in a predetermined plane to said weft-straightening roll, means pivotally mounting each said pair of web-guiding rolls on the frame for independent pivotal movements generally in said predetermined plane of the web approaching said weft-straightening roll thereby to eflect a lateral spreading of the web passing through said pairs of web-guiding rolls, and means pivotally supporting the frame for movement of one end portion of said weftstraightening roll in general direction across the said predetermined plane of the web approaching said wefbstraightening roll thereby to displace one edge portion of the web out of said predetermined plane while the full width of that portion of the web between the guide rolls and the weft-straightening roll is maintained in the same relation to the latter said roll in all positions thereof.

12. In an apparatus for straightening the weft threads in a travelling web of cloth having a roll which is tiltable to simultaneously increase the path of travel of one edge of the Web and decrease the path of travel of the other edge of the web, the combination therewith of webguiding means engaging the opposite edge regions of the web for holding the web in spread condition as the web advances to said tiltable roll, means mounting said web-guiding means for movement with the tiltable roll when the latter is moved to and from any tilted position, whereby the said web-guiding means maintains the edges of the web moving to the tiltable roll approximately in the same spread relation to the tiltable roll in all conditions of the tiltable roll.

13. Apparatus for straightening the weft threads in a travelling web of cloth, comprising a pair of generally parallel guide members disposed with their longitudinal axes in substantially spaced horizontal planes and in substantially spaced vertical planes, a tiltable roll disposed approximately in the horizontal plane of one of said guide members and approximately in the vertical plane of the other of said guide members, whereby a web of cloth engaging said guide members and said tiltable roll engages under one guide member and passes thence to and under said tiltable roll whence it passes to and over the other guide member, making approximately a right-angle change of course at the said tiltable roll, cloth guiding means engaging the opposite marginal portions of the web between the tiltable roll and that guiding member from which the web passes to the tiltable roll, a common tiltable support for said roll and said guiding means, and means pivotally mounting said tiltable support whereby said tiltable roll may be tilted to simultaneously increase and decrease the paths of travel of opposite edge regions of the web between said guide members while said cloth guiding means move with the roll to preserve their original cloth-guiding relations to the roll.

14. In a weft-straightening apparatus. the combination of a weft-straightening roll and means for guiding the opposit edge portions of a web of cloth advancing to 1 roll and adapted to guide the edges of the web for engagement with said roll at predetermined locations between the ends of the roll, a common support for said roll and said web-guiding means, means pivotally mounting said support for movement about an axis transverse of the roll axis and located mid.- way between the ends of said roll, and means for tilting said pivotally mounted means about its pivotal axis thereby to tilt said roll and simultaneously to tilt said web-guiding means so that the latter said means continues to guide the web Number edges to said predetermined locations on the roll in all positions of tilting of the roll.

JOHN D. ROBERTSON.

REFERENCES CITED The following references are of record in the Name Date 1,312,153 Barton "Aug. 15, 1919 2,311,674 Lilja Feb. 23, 1943 2,422,369 Robertson June 17, 1947 

